I had this happen to me last night into today.. My springboard kept constantly crashing after messing around with an app. I found out it was because I wanted to turn an option on for icallannounce - after that that's when my springboard crashed. I had to delete the app, reinstall it and then cydia has the screen to restart the springboard, DONT restart yet.. go to your home screen, settings and undo whatever tweak or option you just made , THEN bring back up cydia and respring. Worked for me after that. I had a problem with that app and facebreak so I don't know, maybe it's an ios 5 thing? not sure

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